2. Name these Features The distance from the center to the edge The distance from one side to the other passing through the center The distance all of the way round the edge The blue line

3. The distance from the center to the edge RADIUS The distance from one side to the other passing through the center DIAMETER The distance all of the way round the edge CIRCUMFERENCE The blue line CHORD Where can you see i) a segment ii) a sector iii) an arc? Sector Segment An ARC is the name for part of the circumference

4. Diameter = 12 cm C = d C = 3.14 X 12 C = 37.68 How to calculate the circumference The symbol is the Greek letter pi. It stands for a number that can never be found exactly. It is approximately 3.14 Evaluate the CIRCUMFERENCE Always, write the formula (rule )

5. Diameter = ?cm C = d d = C ÷ d = C ÷ 3.14 d = 40 ÷ 3.14 d = 12.73 How to calculate the diameter from the circumference If the circumference is 40 cm. evaluate the DIAMETER Always, write the formula (rule )

6. DiameterRadiusCircumference 124 214 317 430 522 6120 778 888 9120 10340

7. DiameterRadiusCircumference 1241275.36 214743.96 33417106.76 46030188.4 5221169.08 612060376.8 715678489.84 817688552.64 938.2219.11120 10108.2854.14340

8. A wheel with a spot of blue paint The wheel turns once This distance is the circumference When a wheel makes one complete revolution, the distance that it travels is its circumference

9. 24ft When a wheel makes one complete revolution, the distance that it travels is its circumference How many times will a wheel with a diameter of 8 feet rotate when it travels distance of 96 feet? 1.Find the circumference of the wheel C = 3.14x 8 ft C = 25.12ft 2. Divide this into 96 to find the number of revolutions Revs 96 ÷ 25.12 Revs = 3.8 or about 4times 96 feet

10. Wheel’s Diameter CircumferenceDistance of Journey Number of Revolutions 3ft63ft 4360 7420 61800 1.Find the circumference of the wheel C = 3.14 x d 2. Divide this into the journey to find the number of revolutions Revs = Journey Distance ÷ C

11. Wheel’s Diameter CircumferenceDistance of Journey Number of Revolutions 3ft9ft63ft7 4ft12ft36030 7ft21ft42020 6ft18ft1800100 1.Find the circumference of the wheel C = 3.14 x d 2. Divide this into the journey to find the number of revolutions Revs = Journey Distance ÷ C

12. A car’s wheels have a diameter of 40 cm. How many times will the wheel revolve during a journey of 1200 cm? Level 8 A bike’s wheels have a diameter of 70 cm. How many times will the wheel revolve during a journey of 630 cm?